Clamping device for an internally separating circular saw blade

ABSTRACT

A clamping device for an internally separating circular saw blade comprising means for clamping the outer edge of the saw blade and an annular fluid-tight pressure chamber having a peripheral edge portion located intermediate the clamped edge portions of the blade and substantially adjacent the blade, said pressure chamber being adapted to receive a fluid medium under pressure such that at least a portion of the blade of the saw is displaced thereby out of its axial plane.

United States Patent 1 Viilki et al.

[ 1 Oct. 2, 1973 CLAMPING DEVICE FOR AN INTERNALLY SEPARATING CIRCULARSAW BLADE [75] Inventors: Walter Viilki, Thun; Alfred Staufier,

Steffisburg, both of Switzerland [73] Assignee: Machineniabrik Meyer &Burger AG, Canton of Berne, Switzerland [22] Filed: July 9, 1971 [21]Appl. No.: 161,198

[30] Foreign Application Priority Data Aug. 7, 1970 Switzerland 11917/70[52] US. Cl 29/105, 269/22, 279/2 [51] Int. Cl B26d 1/12 [58] Field ofSearch 29/105; 269/22;

[56] References Cited UNITED STATES PATENTS 3,656,393 4/1972 Goellner83/698 X 2,652,749 9/1953 Hagmeister 29/105 X 3,250,542 5/1966 Winnen etal 279/2 UX 3,542,354 11/1970 Fitzpatrick 269/22 Primary ExaminerAndrewR. Juhasz Assistant ExaminerLeon Gilden Att0rneylmirie & Smiley 57ABSTRACT A clamping device for an internally separating circular sawblade comprising means for clamping the outer edge of the saw blade andan annular fluid-tight pressure chamber having a peripheral edge portionlocated intermediate the clamped edge portions of the blade andsubstantially adjacent the blade, said pressure chamber being adapted toreceive a fluid medium under pressure such that at least a portion ofthe blade of the saw is displaced thereby out of its axial plane.

4 Claims, 2 Drawing Figures PATENTED Um 2W5 INVENTORS A'e-Hs WALTERVOLK, ALFRED- STAUFF'ER y CLAMPING DEVICE FOR AN INTERNALLY SEPARATINGCIRCULAR SAW BLADE The present invention relates to a clamping devicefor an internally separating circular saw blade,

In a known clamping device, an axial pressure deforms the saw blade.This is produced by a rubber ring located between the saw blade and apressure ring. However, such an arrangement has inherent disadvantages.It requires much skill and time to press the rub-' ber ring uniformlyagainst the saw blade by means of the pressure ring and to thus obtain auniform, gradual deformation of the saw blade without causingeccentricity, imbalance or asymmetry of the clamping effect. Forpractical reasons, the pressure ring is usually screwed firmly against arigid portion of the apparatus. In such a case the tolerances of therubber ring, the supporting surfaces for the rubber ring on the pressurering, and a washer (if used) against which the saw blade is pressed,have an effect on the clamping force. As a result of the elasticity ofthe rubber ring, the clamping of the saw blade is made highly elastic,thus making it substantially impossible to achieve satisfactory clamp-According to the present invention, there is therefore provided aclamping device for an internally separating circular saw bladecomprising means for clamping the outer edge of the saw blade and anannular fluid-tight pressure chamber located substantially adjacent theblade which is adapted to receive a fluid medium under pressure suchthat at least a portion of the blade of the saw is displaced thereby outof its axial plane. The uniform initial tensioning of the saw bladeoffers no difficulties in such a case, since the pressure of thepressure medium always acts uniformly on the entire circumference of thesaw blade. The axial pressure is determined only by the pressure of themedium and differences occurring as a result of tolerances of the rubberring of its associated supporting surfaces such as occur with a knowndevice, do not arise. If a liquid is used as pressure medium, apractically rigid clamping action is obtained.

Preferably there-is additionally provided means for controlling theamount of displacement of the saw blade. Advantageously, the pressurechamber is formed between sealing rings, which rings are in contact withthe saw blade.

Alternatively, the pressure chamber is constituted by an annularresilient tube.

Further preferably, the clamping means comprises a pair of rings whichare interconnected externally of the edge of the saw blade. Furtheradvantageously, one of the rings is provided with an annular groove ofrectangular cross-section, the annular groove being provided with aprotective ring of a soft material and being adapted to receive thedisplaced portion of the saw.

Still further preferably there is additionally provided a pressure ringlocated on the opposed side of the blade to the pressure chamber, whichpressure ring is adapted to be moved against the blade by a plurality ofindependently adjustable screws.

Still further advantageously the pressure ring is slidably displaceablylocated in the annular groove.

The invention will be further described, purely by way of example, withreference to the accompanying drawings, in which:

FIG. 1 is a partial axial section through a clamping device of thepresent invention and FIG. 2 is a partial axial section through a secondembodiment of a clamping device.

The outer edge of an internally separating blade 1 is clamped betweentwo rings 2 and 3 whichare interconnected externally of the outer edgeof the saw blade. In the region of the saw blade, 1, the ring 3 isprovided with an annular groove 4 of rectangular cross-section. Apressure ring 5 is slidably displaceably located in the groove 4 and canbe displaced by means of screws 6. Opposite the groove 4, the ring 2 isprovided with two concentric annular grooves within which the sealingrings 7 are inserted. The frontal portion of the ring 2 is set backbetween the sealing ring 7 and its annular grooves. Accordingly, betweenthe sealing ring 7, the set-back portion of the front of the ring 2 andthe saw blade 1, there is formed an annular chamber 8 adapted to receivea pressure medium such as oil through a valve 9 and a conduit 10.

The saw blade is deformed by this pressure medium I in the region of thepressure chamber 8 and enters the annular groove 4. Since the end of thesaw blade is rigidly clamped between the rings 2 and 3, the saw blade isuniformly tensioned. Previous centering towards the cutting edge 13,effected when the saw blade is clamped between the rings 2 and 3, is notusually lost. However, if a slight deviation of the cutting edge of thesaw blade from the circular form occurs during or subsequent to thetensioning of the saw blade by means of the pressure medium, this can becorrected. In such a case, the pressure ring 5, is pressed against thesaw blade 1 by the individual adjustment of the screws 6 distributeduniformly over the entire circumference of the ring 3. This partiallycompensates for the axial pressure of the pressure medium, andconsequently, any eccentricity thereof is corrected.

A ring 11 of a synthetic material is located against the inner edge ofthe opening of the groove 4, thereby permitting a slight radial movementof the saw blade without excessive friction and wear, since there is ahigh axial pressure at this point.

Since the interconnection of the rings 2 and 3 is effected externally ofthe saw blade, this latter need not be provided with edge perforations.

In FIG. 2, corresponding parts have the same reference numerals as inFIG. 1. However, instead of providing a pressure chamber defined byseals, a flexible tube 12 is provided which can be filled with apressure medium through a valve (not shown). Such an arrangement isparticularly suitable for pneumatic clamping.

I claim:

1. A clamping device for an internally separating circular saw blade,comprising means for clamping the outer edge of the saw blade and anannular fluid tight pressure chamber having a peripheral edge portionlocated intermediate the clamped edge portions of the blade andsubstantially adjacent the blade, said pressure chamber being adapted toreceive a fluid medium under pressure such that at least a portion ofthe blade of the saw is displaced thereby out of its axial plane, andsaid means for clamping said outer edge of said saw blade comprising tworings, said rings being interconnected externally of said outer edge ofsaid saw blade.

2. A clamping device as defined in claim 1 wherein one said ring isprovided with wall portions defining an annular groove of rectangularcross-section, a protective ring of a soft material being located insaid groove, said annular groove being adapted to receive said displacedportion of said saw blade.

3. A clamping device for an internally separating saw blade, comprisingmeans for clamping the outer edge of said saw blade consisting of tworings, said rings being interconnected externally of said outer edge ofsaid saw blade, one said ring having wall portions defining an annularchannel of rectangular cross-section, an annular fluid-tight pressurechamber having a pheripheral edge portion located intermediate theclamped edge portions of the blade and located substantially adsaidblade by independantly adjustable screws.

UNITED STATES" PATENT OF ICE CERTIFICATE OF CORRECTION.

Patent No. 3,762 008 Dated Q t b z 192':

Inveotofls) WALTER VOLKI. et aL It is certified that error appears inthe above-identified patent and that said Letters Patent are herebycorrected as shown below:

In the Heading:

The Assignees correot address is Steffisburg, Canton of.Berne,

Swi tz erla nd Sign'edfand sealed this .9th day ofJuly 1974.

(SEAL) Attest:

C MARSHALL DANN McCOY M. GIBSON; J R. v v I Attesting Officercommlssloner of Patents USCOMM-DC GOING-P69 h u.s. GOVERNMENT PRINTINGomc! I"! o-ass-au FQRM PO-1050 (10-69)

1. A clamping device for an internally separating circular saw blade,comprising means for clamping the outer edge of the saw blade and anannular fluid - tight pressure chamber having a peripheral edge portionlocated intermediate the clamped edge portions of the blade andsubstantially adjacent the blade, said pressure chamber being adapted toreceive a fluid medium under pressure such that at least a portion ofthe blade of the saw is displaced thereby out of its axial plane, andsaid means for clamping said outer edge of said saw blade comprising tworings, said rings being interconnected externally of said outer edge ofsaid saw blade.
 2. A clamping device as defined in claim 1 wherein onesaid ring is provided with wall portions defining an annular groove ofrectangular cross-section, a protective ring of a soft material beinglocated in said groove, said annular groove being adapted to receivesaid displaced portion of said saw blade.
 3. A clamping device for aninternally Separating saw blade, comprising means for clamping the outeredge of said saw blade consisting of two rings, said rings beinginterconnected externally of said outer edge of said saw blade, one saidring having wall portions defining an annular channel of rectangularcross-section, an annular fluid-tight pressure chamber having apheripheral edge portion located intermediate the clamped edge portionsof the blade and located substantially adjacent said blade such that atleast a portion of said blade is displaced thereby out of its axialplane and means for controlling the amount of displacement of said bladesaid means constituted by a pressure ring located on the opposed side ofsaid blade to said pressure chambers wherein said pressure ring isslidably displaceably located in said annular groove.
 4. A clampingdevice as defined in claim 3 wherein, said pressure ring being adaptedto be moved against said blade by independantly adjustable screws.